Coated waterproof sheeting



"WLMU 'JIJUI um iw-tovaailr 13H Patented Apr. 8, 1924.

UNITED STATES tha 1 Mi t. an r n'wau l1 PATENT OFFICE.

nnsrnnmltluafionnnecn, or CHICAGO, ILLrnoIs.

COATED WATERPROOF S'HEETING.

No Drawing. Original application filed February 1, 1919, Serial No. 274,495. New Patent No. 1,464,717.

Divided and. this app1ication filed April a1, Serial No. 463,364.

To all whom it may concern:

Be it known that I, Lnsrnu KIRSCI-IBRAUN, a citizen of the United States, residing in the city of Chicago, county of Cook, and vtit-ate of .lllinois, have invented certain new and useful Improvements in Coated Waterproof Sheeting, of which the following is a specification.

This application is a division of an original application filed by me in the United States Patent Oiiice under date of February 1, 1919, Serial No. 274,495.

This invention relates to improvements in coated Waterproof coverings, such, for example, as roofing, and has among its salient objects, to provide a waterproof felted sheet, to which is applied fibre-containing adhesive coating; to provide a product in which the body or felted portion is preferably waterproofed simultaneously with the formation of the sheet, although in certain cases the body portion may consist of ordinary saturated felt to which is applied the fibre-containing coating; to provide a product which permits of the use of relatively low melting point asphalt as a coating; to provide aproduct in which the coating has a maximum stability and in which the asphalt or bitumen is reinforced against flowing by the fibrous constituents; to provide a product in which very cheap fibre of many different kinds can be used, and in general, to provide an improved prod not and process of the character referred to.

Describing now the preferable wayf of forming the product of the present invention, I make an aqueous mixture of water and an emulsifying agent, such, for example, as a clay containing a suiiicient percentage'of collo'idal particles. To this mixture, and While it is in a heated condition, is added an adhesive binder while in liquid form, such as melted asphalt 01' analogous bitumens or pitches. The binder is thoroughly amalgamated with the emulsifying agent and Water so as to form an emulsified matrix in which the binder is in the internal phase and the emulsifying agent and water in the external phase. This matrix is then intimately mixed with the fibre in a water vehicle. The matrix above referred to may consist, by weight, of fifty parts binder, forty parts water and ten parts clay. This mixture, with the fibre added, may be then passed over an ordinary paper or felt machine. As the sheet is formed, the water dries out and the emulsion is broken and the bitumen becomes adhesive and intimate ly unites with the fibre. The proportion of ingredients in the finished sheet may be as follows: fifty-five per cent of asphalt, eleven par cent of clay and thirty-four per cent of ii re.

After this sheet is formed, as stated, the coating is applied, preferably after the sheet passes over the last drying rolls of the paper machine. The coating mixture, after being formed in the manner hereinafter described, may be applied in the same Way as asphalt coating is applied to ordinary saturated felt. The coating in the present invention, as heretofore stated, consists of bitumen and fibre. Preferably, the coating consists of a mixture of an emulsified matrix and fibre formed in the manner heretofore described, except that a much less percentage of fibre is used. For example, the mixture may consist of ten per cent of fibre, the remainder being asphalt and clay. The emulsion is formed for the reason that the coating can thus be applied cold, but it is not desired to felt the coating;rather, the fibre may be said to more or less float through the asphalt, producing thereby a fibred asphalt coating. For example, a coating of this character may, in some cases, use asphalt for as low as 140 melting point, whereas, ordi narily, from 200 to 260 melting point asphalt is used. Various fibres may be used in this coating, such as cheap fibres ordinarily not suitable for making good paper. After the coating is applied, the sheet is run over drying rolls to remove the water. The bitumen then acts in the manner heretofore described. As the water is driven out, the heated bitumen becomes plastic and a granul ilsc u theme plied to the vex, ating.

claim as my invention:

1. Awaterproof covering consisting of a felted waterproof fibrous sheet saturated with a bitgpiiiious binder and a coating applied to one surface thereof containing bitumen, fibre and an emulsifying agent.

2. A waterproof covering consisting of a felted sheet, a coating applied thereto, said coating containing bitumen, and a minor feltedwsheeti saturated with a Waterproof percentage of fibre and an emulsifying en and a uniting and covering sai coating.

binder connected with a substance containing a major percentage of bitumen and a minor percentage of fibre and an emulsitying agent.

5. A Waterproof covering consisting of a felted sheet saturated with a Waterproof binder, coated with a substance containing a major percentage of bitumen and a minor percentage fibre, and an emulsifying agent, 20

and a llklfiliilitfigillgibolyliieithe329th, 11 g;

LESTER KIRSCHBRAUNQ 

